docs: def run_module(mod_name, init_globals=None,
                 run_name=None, alter_sys=False):
      """Execute a module's code without importing it
  
         Returns the resulting top level namespace dictionary
      """
      mod_name, loader, code, fname = _get_module_details(mod_name)
      if run_name is None:
          run_name = mod_name
      pkg_name = mod_name.rpartition('.')[0]
      if alter_sys:
          return _run_module_code(code, init_globals, run_name,
                                  fname, loader, pkg_name)
      else:
          # Leave the sys module alone
          return _run_code(code, {}, init_globals, run_name,
                           fname, loader, pkg_name)